ICE: due to certain invalid function definitions (nightly)

[trrk]

Code

fn f(_: &＆()) -> &() { todo!() }

Meta

rustc --version --verbose:

rustc 1.65.0-nightly (2befdefdd 2022-08-06)
binary: rustc
commit-hash: 2befdefdda0f2bc5ff93f7f95633c98841409098
commit-date: 2022-08-06
host: x86_64-unknown-linux-gnu
release: 1.65.0-nightly
LLVM version: 14.0.6

ICE does not occur on stable rustc 1.62.1 (e092d0b 2022-07-16)

Error output

error: unknown start of token: \u{ff06}
 --> ./ice.rs:1:10
  |
1 | fn f(_: &＆()) -> &() { todo!() }
  |          ^^
  |
help: Unicode character '＆' (Fullwidth Ampersand) looks like '&' (Ampersand), but it is not
  |
1 | fn f(_: &&()) -> &() { todo!() }
  |          ~

error[E0106]: missing lifetime specifier
 --> ./ice.rs:1:18
  |
1 | fn f(_: &＆()) -> &() { todo!() }
  |         -----     ^ expected named lifetime parameter
  |
  = help: this function's return type contains a borrowed value, but the signature does not say which one of argument 1's 2 lifetimes it is borrowed from
thread 'rustc' panicked at 'assertion failed: bpos.to_u32() >= mbc.pos.to_u32() + mbc.bytes as u32', compiler/rustc_span/src/lib.rs:1683:17
stack backtrace:
   0:     0x7f29c1cb59f0 - std::backtrace_rs::backtrace::libunwind::trace::h6e22058fb33adb17
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   1:     0x7f29c1cb59f0 - std::backtrace_rs::backtrace::trace_unsynchronized::hd2a1708e61390146
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f29c1cb59f0 - std::sys_common::backtrace::_print_fmt::h279555c85be93dc7
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7f29c1cb59f0 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hb103866d42597006
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7f29c1d113bc - core::fmt::write::h65cdd05e60840670
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/core/src/fmt/mod.rs:1198:17
   5:     0x7f29c1ca6b35 - std::io::Write::write_fmt::h6db646eaa1d8d447
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/io/mod.rs:1672:15
   6:     0x7f29c1cb86d1 - std::sys_common::backtrace::_print::hce78bda9ee4db100
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7f29c1cb86d1 - std::sys_common::backtrace::print::hc07e25cf5abe9c56
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7f29c1cb86d1 - std::panicking::default_hook::{{closure}}::hd1d262d7a89d9e55
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:295:22
   9:     0x7f29c1cb839e - std::panicking::default_hook::h1aa381b883c22d14
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:314:9
  10:     0x7f29c452f414 - rustc_driver[9393f240b41885ec]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7f29c1cb8f06 - std::panicking::rust_panic_with_hook::h1d2a753dbad88ac0
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:702:17
  12:     0x7f29c1cb8d19 - std::panicking::begin_panic_handler::{{closure}}::h96d5efaf960fd156
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:586:13
  13:     0x7f29c1cb5f14 - std::sys_common::backtrace::__rust_end_short_backtrace::hc4f6a98ef8d244f2
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys_common/backtrace.rs:138:18
  14:     0x7f29c1cb8a82 - rust_begin_unwind
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:584:5
  15:     0x7f29c1d0de93 - core::panicking::panic_fmt::he8162c4cfec2b07d
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/core/src/panicking.rs:142:14
  16:     0x7f29c1d0dcdd - core::panicking::panic::h1d7951b3e0afb05e
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/core/src/panicking.rs:48:5
  17:     0x7f29c346b4e4 - <rustc_span[6b42ef738fc0c264]::source_map::SourceMap>::lookup_char_pos
  18:     0x7f29c423e872 - <rustc_span[6b42ef738fc0c264]::source_map::SourceMap>::is_valid_span
  19:     0x7f29c423da43 - <core[9bfae4689ad27710]::iter::adapters::cloned::Cloned<core[9bfae4689ad27710]::iter::adapters::filter::Filter<core[9bfae4689ad27710]::slice::iter::Iter<rustc_errors[d49dde1887ca2fa8]::Substitution>, <rustc_errors[d49dde1887ca2fa8]::CodeSuggestion>::splice_lines::{closure#0}>> as core[9bfae4689ad27710]::iter::traits::iterator::Iterator>::try_fold::<(), core[9bfae4689ad27710]::iter::traits::iterator::Iterator::find_map::check<rustc_errors[d49dde1887ca2fa8]::Substitution, (alloc[445b2d6707453a96]::string::String, alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionPart>, alloc[445b2d6707453a96]::vec::Vec<alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionHighlight>>, bool), &mut <rustc_errors[d49dde1887ca2fa8]::CodeSuggestion>::splice_lines::{closure#1}>::{closure#0}, core[9bfae4689ad27710]::ops::control_flow::ControlFlow<(alloc[445b2d6707453a96]::string::String, alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionPart>, alloc[445b2d6707453a96]::vec::Vec<alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionHighlight>>, bool)>>
  20:     0x7f29c423d78a - <alloc[445b2d6707453a96]::vec::Vec<(alloc[445b2d6707453a96]::string::String, alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionPart>, alloc[445b2d6707453a96]::vec::Vec<alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionHighlight>>, bool)> as alloc[445b2d6707453a96]::vec::spec_from_iter::SpecFromIter<(alloc[445b2d6707453a96]::string::String, alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionPart>, alloc[445b2d6707453a96]::vec::Vec<alloc[445b2d6707453a96]::vec::Vec<rustc_errors[d49dde1887ca2fa8]::SubstitutionHighlight>>, bool), core[9bfae4689ad27710]::iter::adapters::filter_map::FilterMap<core[9bfae4689ad27710]::iter::adapters::cloned::Cloned<core[9bfae4689ad27710]::iter::adapters::filter::Filter<core[9bfae4689ad27710]::slice::iter::Iter<rustc_errors[d49dde1887ca2fa8]::Substitution>, <rustc_errors[d49dde1887ca2fa8]::CodeSuggestion>::splice_lines::{closure#0}>>, <rustc_errors[d49dde1887ca2fa8]::CodeSuggestion>::splice_lines::{closure#1}>>>::from_iter
  21:     0x7f29c42397fc - <rustc_errors[d49dde1887ca2fa8]::emitter::EmitterWriter as rustc_errors[d49dde1887ca2fa8]::emitter::Emitter>::emit_diagnostic
  22:     0x7f29c2f854c1 - <rustc_errors[d49dde1887ca2fa8]::HandlerInner>::emit_diagnostic
  23:     0x7f29c2ecf8b1 - <rustc_errors[d49dde1887ca2fa8]::Handler>::emit_diagnostic
  24:     0x7f29c36ba20d - <rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed as rustc_errors[d49dde1887ca2fa8]::diagnostic_builder::EmissionGuarantee>::diagnostic_builder_emit_producing_guarantee
  25:     0x7f29c49b4bb5 - <rustc_resolve[c25bd41e1b9bf380]::late::LateResolutionVisitor>::report_missing_lifetime_specifiers
  26:     0x7f29c3cbfb6e - <rustc_resolve[c25bd41e1b9bf380]::late::LateResolutionVisitor as rustc_ast[45f7db37578a1d11]::visit::Visitor>::visit_fn
  27:     0x7f29c3cb5a76 - rustc_ast[45f7db37578a1d11]::visit::walk_item::<rustc_resolve[c25bd41e1b9bf380]::late::LateResolutionVisitor>
  28:     0x7f29c3ca67ab - <rustc_resolve[c25bd41e1b9bf380]::late::LateResolutionVisitor>::resolve_item
  29:     0x7f29c3ca49e3 - <rustc_resolve[c25bd41e1b9bf380]::late::LateResolutionVisitor as rustc_ast[45f7db37578a1d11]::visit::Visitor>::visit_item
  30:     0x7f29c3d12526 - <rustc_resolve[c25bd41e1b9bf380]::Resolver>::late_resolve_crate
  31:     0x7f29c3d11e5a - <rustc_session[458be8671d45b01d]::session::Session>::time::<(), <rustc_resolve[c25bd41e1b9bf380]::Resolver>::resolve_crate::{closure#0}>
  32:     0x7f29c3d0ed17 - <rustc_interface[d2cd9155816b2322]::passes::boxed_resolver::BoxedResolver>::access::<<rustc_interface[d2cd9155816b2322]::queries::Queries>::expansion::{closure#0}::{closure#0}, core[9bfae4689ad27710]::result::Result<rustc_ast[45f7db37578a1d11]::ast::Crate, rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>
  33:     0x7f29c3d00a4d - <rustc_interface[d2cd9155816b2322]::queries::Queries>::expansion
  34:     0x7f29c3cfe23d - <rustc_interface[d2cd9155816b2322]::interface::Compiler>::enter::<rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}::{closure#2}, core[9bfae4689ad27710]::result::Result<core[9bfae4689ad27710]::option::Option<rustc_interface[d2cd9155816b2322]::queries::Linker>, rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>
  35:     0x7f29c3cf1dba - rustc_span[6b42ef738fc0c264]::with_source_map::<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_interface[d2cd9155816b2322]::interface::create_compiler_and_run<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}>::{closure#1}>
  36:     0x7f29c3cf1790 - rustc_interface[d2cd9155816b2322]::interface::create_compiler_and_run::<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}>
  37:     0x7f29c3cefb01 - <scoped_tls[5d1f420e4e0501fc]::ScopedKey<rustc_span[6b42ef738fc0c264]::SessionGlobals>>::set::<rustc_interface[d2cd9155816b2322]::interface::run_compiler<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}>::{closure#0}, core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>
  38:     0x7f29c3cef7ef - std[40f8087a26b08a14]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[d2cd9155816b2322]::util::run_in_thread_pool_with_globals<rustc_interface[d2cd9155816b2322]::interface::run_compiler<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}>::{closure#0}, core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>::{closure#0}, core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>
  39:     0x7f29c4356059 - <<std[40f8087a26b08a14]::thread::Builder>::spawn_unchecked_<rustc_interface[d2cd9155816b2322]::util::run_in_thread_pool_with_globals<rustc_interface[d2cd9155816b2322]::interface::run_compiler<core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>, rustc_driver[9393f240b41885ec]::run_compiler::{closure#1}>::{closure#0}, core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>::{closure#0}, core[9bfae4689ad27710]::result::Result<(), rustc_errors[d49dde1887ca2fa8]::ErrorGuaranteed>>::{closure#1} as core[9bfae4689ad27710]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  40:     0x7f29c1cc2ed3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hd4035fcb7b1b4c54
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/alloc/src/boxed.rs:1935:9
  41:     0x7f29c1cc2ed3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hf1d2cc2f290c0538
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/alloc/src/boxed.rs:1935:9
  42:     0x7f29c1cc2ed3 - std::sys::unix::thread::Thread::new::thread_start::he51bce15f74442ae
                               at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/sys/unix/thread.rs:108:17
  43:     0x7f29c1b90609 - start_thread
  44:     0x7f29c1ab5133 - clone
  45:                0x0 - <unknown>

error: internal compiler error: unexpected panic

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.65.0-nightly (2befdefdd 2022-08-06) running on x86_64-unknown-linux-gnu

query stack during panic:
end of query stack
error: aborting due to previous error

For more information about this error, try `rustc --explain E0106`.

Backtrace

error: unknown start of token: \u{ff06}
 --> ./ice.rs:1:10
  |
1 | fn f(_: &＆()) -> &() { todo!() }
  |          ^^
  |
help: Unicode character '＆' (Fullwidth Ampersand) looks like '&' (Ampersand), but it is not
  |
1 | fn f(_: &&()) -> &() { todo!() }
  |          ~

error[E0106]: missing lifetime specifier
 --> ./ice.rs:1:18
  |
1 | fn f(_: &＆()) -> &() { todo!() }
  |         -----     ^ expected named lifetime parameter
  |
  = help: this function's return type contains a borrowed value, but the signature does not say which one of argument 1's 2 lifetimes it is borrowed from
thread 'rustc' panicked at 'assertion failed: bpos.to_u32() >= mbc.pos.to_u32() + mbc.bytes as u32', compiler/rustc_span/src/lib.rs:1683:17
stack backtrace:
   0: rust_begin_unwind
             at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/std/src/panicking.rs:584:5
   1: core::panicking::panic_fmt
             at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/core/src/panicking.rs:142:14
   2: core::panicking::panic
             at /rustc/2befdefdda0f2bc5ff93f7f95633c98841409098/library/core/src/panicking.rs:48:5
   3: <rustc_span::source_map::SourceMap>::lookup_char_pos
   4: <rustc_span::source_map::SourceMap>::is_valid_span
   5: <core::iter::adapters::cloned::Cloned<core::iter::adapters::filter::Filter<core::slice::iter::Iter<rustc_errors::Substitution>, <rustc_errors::CodeSuggestion>::splice_lines::{closure#0}>> as core::iter::traits::iterator::Iterator>::try_fold::<(), core::iter::traits::iterator::Iterator::find_map::check<rustc_errors::Substitution, (alloc::string::String, alloc::vec::Vec<rustc_errors::SubstitutionPart>, alloc::vec::Vec<alloc::vec::Vec<rustc_errors::SubstitutionHighlight>>, bool), &mut <rustc_errors::CodeSuggestion>::splice_lines::{closure#1}>::{closure#0}, core::ops::control_flow::ControlFlow<(alloc::string::String, alloc::vec::Vec<rustc_errors::SubstitutionPart>, alloc::vec::Vec<alloc::vec::Vec<rustc_errors::SubstitutionHighlight>>, bool)>>
   6: <alloc::vec::Vec<(alloc::string::String, alloc::vec::Vec<rustc_errors::SubstitutionPart>, alloc::vec::Vec<alloc::vec::Vec<rustc_errors::SubstitutionHighlight>>, bool)> as alloc::vec::spec_from_iter::SpecFromIter<(alloc::string::String, alloc::vec::Vec<rustc_errors::SubstitutionPart>, alloc::vec::Vec<alloc::vec::Vec<rustc_errors::SubstitutionHighlight>>, bool), core::iter::adapters::filter_map::FilterMap<core::iter::adapters::cloned::Cloned<core::iter::adapters::filter::Filter<core::slice::iter::Iter<rustc_errors::Substitution>, <rustc_errors::CodeSuggestion>::splice_lines::{closure#0}>>, <rustc_errors::CodeSuggestion>::splice_lines::{closure#1}>>>::from_iter
   7: <rustc_errors::emitter::EmitterWriter as rustc_errors::emitter::Emitter>::emit_diagnostic
   8: <rustc_errors::HandlerInner>::emit_diagnostic
   9: <rustc_errors::Handler>::emit_diagnostic
  10: <rustc_errors::ErrorGuaranteed as rustc_errors::diagnostic_builder::EmissionGuarantee>::diagnostic_builder_emit_producing_guarantee
  11: <rustc_resolve::late::LateResolutionVisitor>::report_missing_lifetime_specifiers
  12: <rustc_resolve::late::LateResolutionVisitor as rustc_ast::visit::Visitor>::visit_fn
  13: rustc_ast::visit::walk_item::<rustc_resolve::late::LateResolutionVisitor>
  14: <rustc_resolve::late::LateResolutionVisitor>::resolve_item
  15: <rustc_resolve::late::LateResolutionVisitor as rustc_ast::visit::Visitor>::visit_item
  16: <rustc_resolve::Resolver>::late_resolve_crate
  17: <rustc_session::session::Session>::time::<(), <rustc_resolve::Resolver>::resolve_crate::{closure#0}>
  18: <rustc_interface::passes::boxed_resolver::BoxedResolver>::access::<<rustc_interface::queries::Queries>::expansion::{closure#0}::{closure#0}, core::result::Result<rustc_ast::ast::Crate, rustc_errors::ErrorGuaranteed>>
  19: <rustc_interface::queries::Queries>::expansion
  20: <rustc_interface::interface::Compiler>::enter::<rustc_driver::run_compiler::{closure#1}::{closure#2}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_errors::ErrorGuaranteed>>
  21: rustc_span::with_source_map::<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_interface::interface::create_compiler_and_run<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#1}>
  22: rustc_interface::interface::create_compiler_and_run::<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>
  23: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorGuaranteed>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorGuaranteed>>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

error: internal compiler error: unexpected panic

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.65.0-nightly (2befdefdd 2022-08-06) running on x86_64-unknown-linux-gnu

query stack during panic:
end of query stack
error: aborting due to previous error

For more information about this error, try `rustc --explain E0106`.